It's a good thing several days have past, because the timber of this discussion would have been much different, and not in a good way. I was angry. Two new battery chargers were destroyed. One literately went out with a bang, and the second one went out with a whimper after running for a couple of minutes.

I was asked to look at a battery charger that was used to charge two small starter batteries for the generators. This looked straight forward. Out comes my meter. One probe goes onto the green ground wire, and one on the black volt wire. The meter says 120 volts, so it is getting Mr. Electricity. I check the 12 volt output, it's zip, and I pronounce it broke. The owner watching had also checked the AC input. No problems so far. We'll get a new one. The particular unit that was in the boat would have to be ordered, so to expedite I picked another brand I could buy locally. This is not a large unit, and a single five amp output would be fine.

When I was ready to disconnect the charger, I put the meter leads on the green and black wires, and asked the owner to throw the breakers until the power went off, and in a few seconds it did. Out with the old, and in with the new. I went back to the panel, threw the breaker, and kapow. Smoke appeared, and the breaker had popped. Lots of head scratching, and connection checking occurs. All appears fine, so the box must have had a problem. I get a second charger, and the same thing happens again. "Having something like this happen twice in a row, is not a coincidence," comments the owner, and I agree. So I go l back to the 110 volt wire and take a much closer look. It turns out it was never the box, it was the wiring. I had assumed that the 110 volt wire was a 110 volt wire, and it wasn't. After some checking I discover that the neutral white wire is also hot. In the end it turns out that the builder was using 110 volt wire for a 220 volt circuit. I had not noticed that the breaker on the large panel was on the 220 volt side of the panel when I turned it on, twice.

I look at he leads on the charger, and they are marked exactly like a 110 volt circuit should be, but in small print on the the charger label it states it can also use 220 volts. In the manual, there is a small note in section eight, that says if you are using 220 volts, skip the instructions in section 7, and attach the second hot RED lead to the neutral post. What Red wire?

I talk to the factory, and proceed to get a lecture in a calm voice that explains to the very slow witted installer that I should have known that was a 220 circuit, because the breaker was on the 220 side. Okay, that should have been a clue that something was wrong, and I did overlook that, sort of. The gentleman goes on further to explain that most boat chargers are 220 volt, and that's why they prefer to use them. "Huh?" I'm staring at the big bank of 8D batteries that are being charged by a the 110 volt Magna Sine inverter/charger that would have taken two people to hang on the bulkhead. Quite a load of crap was still being pedantically droned at me. I keep my mouth shut while I'm being told there were no problems with their construction, or design until I asked, "Why did you use 110 volt wiring for a 220 circuit?, I mean if the wiring type was correct, none of this would have happened." Silence reigns, and there is no response because the wire used was definitely not the right type.

So I'm going to take the hit for this, but in the course to changing out this system, most cues were saying this was a 110 volt circuit. The lugs on the charger, the type of wire used, the test for power I would do on a 110 volt system all pointed to 110 volts. Why would the huge boat charger be 110 volts, and the tiny 10 amp charger 220 volts? I think the answer is that the 110 volt side was full, so they found a 220 volt charger, put it on the other panel, used the wrong type of wire, and then didn't bother to tag it. And by the way, I have found more than once 110 volt breakers on the 220 side that had been jumpered over because they ran out of room. I ordered a new charger, and after it's installed my label maker will provide a tag for the wrong wire, that the builder couldn't manage do. And for the charger maker, add a fourth lug labeled L2. Neutral should be neutral, and not sometimes L2, if you do step eight in the fine print of the manual. I'm still really really mad.

I cribbed and tweaked a stanza from the Animaniacs cartoon I'm mad. I'm a big fan of these cartoons.

Robert, It would have read 120 volts, but it would have told the story. You're right, and as I said "I'm taking the hit." I did a I have a beard, Abraham Lincoln had a beard thing..... The cues kept pushing me away from the thought that it was a 220 circuit. Had the wire been right, or had the charger lugs indicated 220 wiring was possible, I would have seen it. I just kept thinking that the white wire had to be a neutral, because it was 120 volt wire. I will double check from now on. Or as a client once told me, another memory was made.

I don't blame the builder for using the wire, BUT the builder should have reidentified the white wire using red electrical tape or heat shrink on both ends.

I guess it's habit from doing more 120VAC work than 12VDC work, but I always check the voltage on the load wires. This would have showed 240 and not 120. Hindsight is 20/20 I guess, but now you know that the actual voltage can only be measured between the current carrying conductors :)